Automatically operated refrigerator drip-tray baffle-damper combination



June 21, 1955 E. M. GAUL ETAL 2,711,081

AUTOMATICALLY OPERATED REFRIGERATOR DRIP-TRAY BAFFLE-DAMPER COMBINATION Filed Aug. 17, 1953 C5 Sheets-Sheet 2 INVENTORS.'

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June 2l, 1955 E. M. GAUL ETALv 2,711,081

AUTOMATICALLY OPERATED REFRIGERATOR DRIP-TRAY BAFFLE-DAMPER COMBINATION Filed Aug. 17, 1955' v5 Sheets-Sheet 3 United States Patent() 2,711,081 AUTOMATICALLY OPERATED REFRIGERATOR DRIP-TRAY BAFFLE-DAMPER COMBINATION Edward M. Gaul, Edwin M. Marks, and Walter H, Oldham, Evansville, Ind., assignors to International Harvester Company, a corporation of New Jersey Application August 17, 1953, Serial No. 374,801 7 Claims. (Cl. 62-2) This invention relates to refrigerator cabinets, but more specically to a combined drip-tray and air baille or damper adapted for use in a refrigerator cabinet having compartments maintained at different temperatures and cooled by one evaporator.

Heretofore refrigerator cabinets have been provided wherein there is an upper food-storage compartment that is cooled by an evaporator located therein, and a lower food-storage compartment separated from the other compartment by a drip-tray baille-like partition and cooled by convectional air ow through openings in or around said partition. In structures of this character a damper-like air ow control member is frequently provided to close an opening in the partition between the two co'rnpa'rt'- ments so as to regulate the ow of convectional air currents therebetween and thereby control the temperature of the lower compartment. Motivation of this damper is generally accomplished by manual operation but frequently it is operated by thermostatic means responsive to temperatures existing at one of several selected locations such, for instance, as the ambient temperatures, the

lower compartment temperatures, the upper compartment temperatures, the machinery compartment temperatures or the temperatures of certain parts of the refrigerating apparatus. Although none of these previous arrangements worked out entirely satisfactorily because of one reason or another the use of the lower compartment temperatures for control initiation purposes is believed to be the most desirable.

This latter arrangement, however, has one serious inherent drawback in that a large temperature variation in the lower compartment is necessary before suicient power is generated in the conventional thermostat to actuate the damper. Minimizing this diiculty ordinarily requires either the use of a lightweight delicately balanced damper, an extremely sensitive thermostat, or booster means for physical actuation of the damper, each of which serves only to complicate and increase the cost of the mechanism, in a highly competitive and closely costed product, without exercising or accomplishingV the most effective and proper control over the temperature in the cabinets' lower compartment.

It is the principal object of this invention, thereforei to provide an improved thermostatically operated `damper' device that is effective for controlling the temperature in the lower compartment of a refrigerator Ycabinet in response to temperature variations in said lower compartment.

Another object is to provide an improved airllow control damper assembly adapted for .removable securement to a drip-tray baille slidably positionable beneath a refrigerant evaporator in a refrigerator cabineL l Another object is to provide improved means for controlling the flow of air currents between `the upper` and lower compartments of a refrigerator cabinet,` and wherein said means is thermostatically responsive Ato temperatures in the lower compartment of the cabinet.

A further object is to provide an air flow cont-rol damper assembly in which the damper member is movably mounted on a partition member slidably po'sitionable below a refrigerant evaporator, and wherein the damper is actuated by an improved thermostat likewisel mounted on said partition and directly responsive to temperatures 2,711,081 Patented `Iuine 21, 1955 in the lower of two food storage compartments in a refrigerator cabinet.

A still further object is to provide a compact, inexpensive air flow control means having a rotatable damper and a thermostatically responsive device for the actuation thereof and to have said means removably aixed to a partition member adapted for Vslidable positioning between the upper and lower compartments in a refrigerator cabinet.

A yet still further object is to provide novel air ow control means for a compartmentized refrigerator cabinet wherein an improved type of thermostatic device, responsive to temperatures in the lower of two compartments in the refrigerator, is utilized to actuate a damper member that is rotatable into a plurality of positions in an air passage between two compartments therein for controlling the ow of air therebetween.

An important object is to provide an improved refrigerator cabinet air tlow control means wherein a thermostatic device, responsive to temperature variations in one compartment of the refrigerator, rapidly translates its small magnitude reaction to these variations through quick acting motion amplifying means to a damper member that operates without appreciable time lag to regulate air flow between compartments of the cabinet, and by so doing functions to maintain a substantially consta'nt temperature in the compartment in which the thermostatic device is located.

The foregoing and other objects and features of the invention Willbecome apparent as the disclosure is more fully made in the following detailed description of a preferred embodiment of the invention as illustrated' in the accompanying drawings in which:

Fig. l is a front elevation of a portion of a refrigerator cabinet incorporating the present invention;

Fig. 2 is a sectional side elevation view of the portion of a refrigerator cabinet shown in Fig. 1;

Fig. 3 is a top elevation view of an improved drip-tray with a damper and its thermostatic control mechanism shown incorporated therein;

Fig. 4 is an end elevation view of an improved droptray, partition fashioned 'according to the present invention and with 'the cover for the thermostatic control device associated therewith broken away;

Fig.l 5 an elevational view in enlarged dimension of a portion "of the drip-tray and damper showing the rear wall hinge mounting for the damper;

Fig. 6 is a sectional View of the thermostatic control mechanism for the damper, and taken on line 6 6 of Fig; 3;-and

Fig. 7 is a bottom view mechanism for the damper, therefor shown as cut away. Y

AA preferred embodiment of the present invention is illustrated 'as incorporated in a Yconventional household refrigerator wherein a cabinet 10 includes 'an inner liner llformed with a top wall 11a, rear wall 11b, a pair of side Walls 11e, and a bottom wall (not shown),` sepa'rated, by suitable insulating material 12, from a similarly formed outer liner 13 with the space between the marginal edges of said liners covered with a breaker strip member 14,- and having a closure member such as the door 1 5 hingedly aflixed 'to a front portion thereof.` The inner liner l1V encloses and together with the door V15a defines afood storage space within the l `:abinet which may be divided into an upper compartment 16,-- and a lower compartment '17 separated therefrom by a drip-tray baffle or partition member, indicated generally by the reference numeral 18', which is slidably positioned on v,guide rails 19 mounted on Ythe `side walls ofl said inner'linen The upper compartment 16 is cooled by a conventional evaporator 20 which yextends 'across the' top tliereo'fland'reof the thermostatic control with portions of the cover ceives compressed refrigerant from refrigerating apparatus generally located in the lower portion of cabinet (not shown), while the evaporator may be provided with a hinged closure such as the door 21. The evaporator normally is spaced from the rear wall 11b and from the closure door 15 thereby providing passages 20a and 20h, respectively, in the rear and front of said compartments through which air may circulate from one compartment to another.

The partition member 1S is fashioned, preferably', in the form of a drip-tray 22 having an insulated bottom wall 23, opposite side walls 24, front wall 25, arid rear wall 26 all upstanding therefrom, while a peripherally extending rim 26a may also be provided along the upper edge of said walls. The insulated bottom wall v23 includes a substantially flat lower oor member 27 separated by insulating material 28 from an upper moisture-collecting floor member 29 which, for drainage purposes, slopes in all directions toward an opening 3G in said bottom. ln the illustrative embodiment the drip-tray 22 is shown as fashioned from a plastic material but it will be understood other materials, such as glass, rubber, and stainless steel among others, may be used without deviating from the primary concepts of the present invention. A gen-` erally conventional meat pan 31 may, if desired, be slidably suspended beneath said drip-tray by any suitable means such as the slide rails 32 secured to said bottom wall. On the rear wall 26 of said drip-tray, and preferably fashioned integral therewith, are two laterally spaced projecting abutment lugs or hinge supports 33 the purpose of which will be apparent hereinafter.

Now in accordance with the more specific teachings of the present invention, a damper or air flow control member is mounted for pivotal movement about-the rear wall 26 of said drip-tray. Said damper is fashioned as a relatively thin, tlat and light-weight shutter member 34 and has affixed thereto twopair of angularly extending hinge members 35 which are disposed with one pair proximate each end thereof, and with the individual portions of each pair slightly spaced from one another. These hinge members, perferably, are fashioned integral with the damper member, although they may be fabricated separately and aflixed thereto by any well known means, and they are disposed so that one such pair maystraddle each rear Wall hinge support or projecting lug member 33 and a pivotal pin 36 may be positioned in aligned openings therethrough to pivotally secure said damper to the drip-tray rear wall. of the damper member 34 and disposed proximate one pair of said hinge members is a bracket member 37 which, in turn, is pivotally aixed, by suitable means such as the pivot pin 38, to an actuating lever 39.

A supporting base or panel member 40 is secured, by suitable means such as the screws 41, to the lower oor member 27 of said drip-tray bottom wall and is provided with flanges 42, 43, 44, and 46 turned over from yand extending normal to the edges thereof. A canopylike bonnet 47 covers said base member and many of the components supported thereon and may be aixed to the base by suitable means such as the screws 48 which are threadably received in the flanges 43 and 45. A slotted opening 49 in one wall of said cover slidably accommodates the actuating lever 39 which also passes through a similar opening 50 in the flange 43.

The end of the actuating lever 39 opposite from that pivotally aixed to the damper is provided with an elongated yoke portion, as indicated at 51, and each arm of the yoke is outwardly turned at its end to form a flange 52 and the two anges thus formed cooperate to fashion a shoulder-like abutment or stop for one end of an over-travel coil spring 53 the convolutions of which surround said yoke portion. One end of an actuating lever extension 54 is telescopingly received in the yoke portion 51, of the actuating lever 39, and is fashioned with outwardly turned flanges, as indicated at 55, to pro- Depending from one wall surface vide an abutment or stop for the opposite end of said coil spring. As thus disposed, the spring may be cornpressed, between the shoulder-like'abutments or stops formed by said flanges 52 and 55, to absorb excess motion of an actuating arm or link and thus prevent excessive downward travelV of the damper member 34. The

opposite end of the extension member S4 is provided with a yoke portion 56 which, together with the pivot pin Y 57, pivotally secures said member to a transverse link member 58 at a point spaced from the end thereof. The end of said link member has a shoulder 58a provided therein that may abut a stop ange 5819, fashioned from the upstanding ange 44, upon rotation of said link member as hereinafter explained. The opposite end of said link is pivotally mounted on a pintle pin or stud 59 which, in turn, is afxed to the base member 40, while the free end of said stud extends through an opening in a bent over end portion of the flange 46 to provide a bight-like stop or guide means for preventing the link from slipping off the end of the stud. If desired, the end of said stud may be peened over or otherwise suitably anchored to provide a more rugged and secure construction. A sleeve bushing or spacer block 60 positioned around the stud 59 serves to space the link 58 fromfthe base member 40 and additionally provides a bushing for a retraction` spring. Intermediate the ends of the link 58 is connected one end of a torsional retractionspring 61, the convolutions fof Which surround the sleeve bushing 60, while the opposite end thereof abuts the edge of the ange'42. A thermostatic device, indicated generally by the reference numeral 62, is threadably mounted by means of a threaded sleeve 63 in a threaded boss 64 aflixed toV the ilange 42. Said thermostatic device has an operating piston or plunger projecting fromV one end thereof.

67 provides means for manually turning or rotating said thermostat in its mounting in order to vary the temperature setting thereof. As the knob 67 is turned the threaded portion 63 advances or recedes into or out of the threaded boss 64 to change the force that the plunger 65 exerts against shoulder 66 under different temperature conditions. In this Way the temperature settings at which the damper member 34 is actuated may be varied, as desired, by the user to meet changing conditions. A thermostatic device of the character shown and described is presently manufactured by the Detroit Controls Corporation and is sold commercially under the trade designation of Vernatherm. characteristicsrof this device that makes it particularly suitable for the application proposed herein is the fact that a relatively heavy force is requiredk to return the piston to positionr'after the temperature which caused the initial expansion of the piston has receded, Because of this characteristic a relatively strong spring 61 is provided to effect this return. The use of such a spring, however, offers the advantage that the mechanism may be returned and the damper actuated upon a temperature change without the usual noticeable time lag that' is customarily an inherent feature of the thermostatic devices heretofore employed for such purposes. This rapid return and damper control action is highly effective in maintaining a more constant temperature in the lower compartment and is one of the features of the present invention which readily distinguishes it from prior de-Y vices of this character.

In the proposed arrangement it was found that a 20V pound spring would accomplish the desired action although deviations from this specific value may be found to be desirable for different installations; hence it is not intended that the present invention be limited to such specilic application, Another feature which distinguishes this device is the absence of the feeler bulb, which One of the Ordinarily would have to be connected by a conduit to the power element of the thermostat, and which, when present, would interfere with the ready removal of the air iiow control mechanism from the cabinet.- In the proposed arrangement the control mechanism is compactly arranged and secured to the drip tray for removal therewith.

Normally the thermostatic device 62 is adjustedv so that when the desired temperature prevails in the lower compartment 17 the plunger or piston 65 of said device is withdrawn because of contraction of the responsive medium therewithin, and hence the link 58,` urged by the reactive force of the torsional spring 61, is rotated clockwise (as viewed in Fig. 3) about its pivotal stud 59 to force the actuating lever 39 rearwardly thereby rotating the damper, 34 into a substantially horizontal position. The stop 58h serves to prevent the linkage and damper mechanism from being moved beyond a desired position, particularly when the lower compartment is unusually cold. With the damper in the horizontal position the air flow passage 26a, adjacent the rear wall 11b of the inner liner, is substantially closed oli and the circulation of air through the cabinet, accordingly, is considerably restricted. Ordinarily cooled air from the upper cooled or evaporator compartment 16 liows down through the rear passage a and after being warmed by picking up heat from the lower compartment 17 ows upwardly through the forward passage 20b, and back intoI heat exchange relation with the evaporator cooler 20 where it is recooled before repeating its circulation cycle. Upon restriction of the rear passage 29a the circulation of air throughout the cabinet is, of course, considerably reduced and usually the temperature of said lower compartment rises as a result thereof. When this occurs the highly sensitive and rapidly reacting thermostatic device 62 operates to force its plunger 65 forward and hereby rotate the link 58, in a counterclockwise direcion (as viewed in Fig. 3) about its pivotal stud 59, and to move the actuating lever 39 forward and thus rotate the damper 34 to the downwardly extending position where it does not appreciably interfere with the free circulation of air through the rear passage 20a. The bumper or shock-absorbing over-travel spring 53 serves to prevent over controlling or damage to this mechanism when the temperature is high, such as mightbe encountered during' shipping or storage or during periods of high ambients or when there are numerous door openings which raise the lower compartment temperature. After the temperature of Ythe lower compartment has beeny reduced to a desired degree, said thermostatie device acts to draw in or retract its plunger and, assisted by the reactive force of the torsional spring 61, functions to rapidly reposition said damper across the rear passage 20a to again restrict the iiow of cooled air throughout the cabinet'.

From the foregoing it will now be obvious that the present invention provides an improved air iiow control means, particularly adaptable for regulating the iiow of convectional currents between compartments in a refrigerator, and that said means is responsive without any appreciable time lag to the temperature variations in the lower of two contiguous compartments for maintaining the lower compartment thereof at a substantially constant temperature. Likewise the temperature of the lower compartment is maintained substantially constant regardless lof variations in ambient temperatures. Furthermore, the air iiow control means is entirely r'nounted on a drip-tray partition member which, in turn, is easily removable lfrom the refrigerator cabinet for cleaning, adjustment, or like purposes. In addition, the control device is simple, inexpensive, easily adjustable to provide lower cabinet temperatures and is readily adaptable for incorporation in a modern refrigerator cabinet. A further advantage resides in the fact that faster recovery is n'ow provided from sudden loads such as might result from door openings or from the introduction of storage loads into ythe cabinet.l

While only one form of the invention has been shown,

am Lost! 6 it will be obvious to those skilled'in the art that it not so limited, but is susceptible of various changes and moditications without departing from the spirit thereof, and it is desired, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What is claimed is:

l. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottom walls, and a vertical door defining at least a part of the front wall of said chamber; a partition slidably positioned in said chamber dividing it into an upper and a lower compartment; an evapo= rator cooling unit in said upper compartment; said charnber having a iirst air passage located near said door and a second' air passage located near said rear wall to provide circulation of air between said upper and lower compartments; a damper movably mounted on saidpartition. and positionable across said second passage for controlling the flow of air through said second passage; a thermostat carried bysaid partition and responsive to variations in temperature of the lower compartment; andl motion amplifying means removably carried by said partition and operatively connecting said thermostat to said damper, whereby the position of the damper across the second air passage may rapidly be varied in accordance with small temperature variations in the lower compartment. Y Y

2. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottoni walls, and a vertical door defining at least a part of the front wall of said chamber; a drip-tray having upstanding front, rear, and side walls, and a double walled bottom with insulation between said double bottom walls; said drip-tray being slidably positioned in said chamber and extending 'sub-- stantially to the side walls thereof and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a first air passage located near said door and a second air passage located near the rear wall of the chamber for circulating air between said upper and lower compartments; air flow control means for restricting the iiow of air through said second passage; said air liow control means being carried by said drip-tray and including, an elongated damper pivotally mounted on the 'rear wall of said drip-tray and extending into said second air passage, a base panel removably aiiixed to the exterior bottom wall of said drip-tray, a thermostat responsive to the temperature of the lower compartment 'and aiiixed to said base panel, and linkage mechanism pivotally mounted on said base panel and operatively connecting said thermostat to said damper for operatively controlling the position of said damper with respect to said second air passage, whereby the flow of air through said second air passage is adjusted according to the tem-V perature of said lower compartment.

3. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottom walls, and a vertical door defining at least apart of the front wall of sai'd chamber; a drip-tray having upstanding front, rear, and side walls, and a bottom wall; said drip-tray being slidably positioned in said chamber and extending substan- 'tially to the side walls thereof, and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a rst air passage located near said door and a second air passage located near' the rear wall of the chamber for circulating air between said upper and lower compartments; air ow control means for restricting the ow of air through said second passage; said air iiow control means being carried by said drip-tray and including, a damper pivotally mounted on the rear wall of said drip-tray and extending into said second air passage, a base vmember adapted for afxment to the bottom wall of said drip-tray, a thermostat responsive to the 'temperature of the lower compartment and adjustably mounted on said base member and having said thermostat rotatable in said adjustable mounting so that the actuating temperature setting thereof is adjusted according to the degree of rotation of said thermostat in the mounting, and linkage mechanism pivotally carried by said base and adapted for transmitting motion of an operating element of said thermostat to said damper for operatively controlling the position of said damper with respect to said second air passage, whereby the ow of air through said second air passage is controlled by the temperature of said lower compartment.

4. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottom walls, and a vertical door defining at least a part of the front wall of said chamber; a drip-tray having opstanding front, rear, and side walls, and an insulated bottom wall; said drip-tra3r being slidably positioned in said chamber and extending substantially to the side walls thereof and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a first air passage located near said door i' and a second air passage located near the rear wall of the chamber for circulating air between said upper and lower compartments; a horizontally extending damper pivotally mounted along one of its edges to the rear wall of said drip-tray, and being rotatable into a position such that its largest surface substantially subtends the area of said second passage and restricts the ilow of air therethrough; a support base removably aixed to the exterior bottom wall of said drip-tray; a iirst lever pivotally mounted at one end thereof on said base, the opposite end thereof being free to rotate about said pivotal mounting; means connecting the free end of said lever pivotally to said damper; a thermostat responsive to the temperature of the lower compartment and secured to said base; said thermostat having an operating element thereof that engages said lever at a point adjacent the pivotally mounted end of said lever, whereby said thermostat is operable for controlling the position of said damper in accordance with the temperature of the said lower compartment.

5. A refrigerator, comprising: an insulated chamber having top7 side, rear, and bottom walls, and a vertical door defining at least a part of the front wall of said chamber; a drip-tray having opstanding front, rear, and Side walls, and a bottom wall; said drip-tray being slidably positioned in said chamber and extending substantially to the side walls thereof, and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a first air passage located near said door and a second air passage located near the rear wall'of the chamber for circulating air between said upper and lower compartments; a damper pivotally mounted along one edge thereof to the rear wall of said drip-tray, and being rotatable into a position such that it extends across the area of said second passage for restricting the ilow of air therethrough; a mounting base adapted for securement to the bottom of said drip-tray; a first lever pivotally mounted proximate one end thereof on said mounting base, the opposite end thereof being free to rotate about said pivotal mounting; a second lever pivotally secured at one end thereof to said first lever proximate the free end thereof; a third lever pivotally mounted at one end thereof to said damper; resilient means interlocking the free ends of said second and third levers; a thermostat responsive to the temperature of the lower compartment and adiustably secured to said mounting base; and having said thermostat operatively connected to said first lever, whereby said thermostat is operable for controlling the position of said damper in accordance with the temperature of vsaid lower compartment.

6. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottom walls, and a vertical door defining at least a part of the front wall of said chamber; a drip-tray having upstanding front, rear, and side walls, and a bottom wall', seid drip-tray being slidably positioned in said chamber and extending substantially to the side walls thereof, and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a first air passage located near said door and a second air passage located near the rear wall of the chamber for circulating air between said upper and lower compartments; a damper pivotally mounted along one edge thereof to the rear Wall of said drip-tray, and being rotatable into a position such that it extends across the area of'said second passage for restricting the flow of air therethrough; a mounting base adapted for securement to the bottom of said drip-tray; a lever pivotally mounted proximate one end thereof on said mounting base, the opposite end being free to rotate about said pivotal mounting; means pivotally connecting said lever with said damper including, a first member pivotally connected at one end to said damper and having a yoke at the opposite end with a stop iiange at the end of each portion of said yoke, a second member pivotally connected at one end to said lever the opposite end being provided with a stop flange and adapted for telescoping into the yoke of said iirst member, a resilient member disposed between the flanged ends of said tirst and second i members whereby in one direction of movementof said means said second member engages said first memberk to actuate said damper and in movement in the opposite direction the anges of said rst and second members cooperate to compress the resilient member and prevent excessive movement of said damper; a thermostat responsive to the temperature of the lower compartment and removably mounted on said mounting base; and having said thermostat operatively connected to said lever,

whereby said thermostat is operable for controlling the position of said damper in accordance with the tempera-Y tune of said lower compartment,

7. A refrigerator, comprising: an insulated chamber having top, side, rear, and bottom walls, and a vertical door defining at least a part of the front wall of said chamber; a drip-tray having upstanding front, rear, and side walls, anda bottom wall; said drip-tray being slidably Ypositioned in said chamber and extending substantially to the side walls thereof, and dividing said chamber into an upper and a lower compartment; an evaporator cooling unit in said upper compartment; said chamber having a vtirst air passage located near said door and a second air passage located'near the rear wall of the Chamber for circulating air between said upper and lower compartments;`a damper pivotally mounted along one edge thereof to the rear Wall of said drip-tray, and being rotatable into a position such that it extends across the area of said second passage for restricting the flow of air therethrough; a mounting base adapted for securenient to the' bottom of said drip-tray; a lever pivotally mounted proximate one end thereof on said mounting base, the opposite end being free to rotate about said pivotal mounting; means connecting the free end of said lever to said damper; resilient means circumscribing said pivotal mounting and disposed so as to rotatably urge said lever about said pivotal mounting; said lever being fashioned with a notched portion on the end thereof adjacent said pivotal mounting; a thermostat responsive to the temperature of the lower compartment and removably secured to said mounting base; said thermostat having an operating element that engages the notched end portion of said lever and rotates said lever against the action of said resilient means whereby said thermostat is operable for controlling the position of said damper in accordance with the temperature of said Vlower compartment.

Atchison Nov. 2l, 1939 2,292,032 Atchison Aug. 4, 1942 2,645,909V Philipp July 2l, 1953 

